git cl: warn when landing on chromium/src branch-heads.

Undos a hack added while CQ for branches was experimental.

R=ehmaldonado

Bug: 1043225, 753213
Change-Id: Ie88b61e61f59e828f0ac4a36cf4e356700305482
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/tools/depot_tools/+/2011308
Auto-Submit: Andrii Shyshkalov <tandrii@google.com>
Commit-Queue: Edward Lesmes <ehmaldonado@chromium.org>
Reviewed-by: Edward Lesmes <ehmaldonado@chromium.org>

git_cl.py

@@ -2088,14 +2088,7 @@ class Changelist(object):
 
   def _IsCqConfigured(self):
     detail = self._GetChangeDetail(['LABELS'])
-    if u'Commit-Queue' not in detail.get('labels', {}):
-      return False
-    # TODO(crbug/753213): Remove temporary hack
-    if ('https://chromium.googlesource.com/chromium/src' ==
-        self.GetRemoteUrl() and
-        detail['branch'].startswith('refs/branch-heads/')):
-      return False
-    return True
+    return u'Commit-Queue' in detail.get('labels', {})
 
   def CMDLand(self, force, bypass_hooks, verbose, parallel):
     if git_common.is_dirty_git_tree('land'):